Angela Klatt

A rising music student Angela Klatt (Susanna Foster) who's singing voice has attracted the unfortunate attention the opera house's doctor, Dr. Hohner (Boris Karloff).

To him she sounds too much like Marcellina (June Vincent), another opera star who vanished from the Vienna Royal Theater mysteriously ten years ago, because she was murdered by Hohner, her lover. From the 1944 film The Climax.